Absorbent article providing improved fecal containment

ABSTRACT

An absorbent article has a moisture barrier and an absorbent assembly disposed on the moisture barrier. In one embodiment, fecal containment members of the absorbent article are positioned transversely outward of the absorbent assembly between the absorbent assembly and each longitudinal side edge of the article. The fecal containment members have a wet compression recovery of at least about 85 percent and a mean pore size of at least about 1.5 millimeters.

This application is a continuation of application Ser. No. 08/448,771entitled "ABSORBENT ARTICLE PROVIDING IMPROVED FECAL CONTAINMENT" andfiled in the U.S. Patent and Trademark Office on May 24, 1995, nowabandoned, which is a divisional of application Ser. No. 08/362,611,entitled "ABSORBENT ARTICLE PROVIDING IMPROVED FECAL CONTAINMENT" andfiled in the U.S. Patent and Trademark Office on Dec. 21, 1994. Theentirety of these applications is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates to articles for absorbing body fluids.More particularly, the invention pertains to an absorbent articleproviding improved containment of fecal matter.

Conventional disposable absorbent articles have typically included aliquid pervious bodyside liner, a liquid impervious backing sheet, andan absorbent material disposed between the bodyside liner and thebacking sheet. To improve the fit of the absorbent article about thewearer, and to enhance the containment of waste materials, such productshave also included elastic materials. Most commonly, these elasticmaterials have included threads, strands, or ribbons of elastic bondedto the backing sheet, either along the longitudinal sides or thelongitudinal ends of the product.

Absorbent articles are called upon to contain both liquid waste andfecal matter. The fecal matter is often highly fluidic and expelled athigh velocities. Although conventional fit and containment structuresmay function well to absorb and contain liquid waste, they do notnecessarily function effectively with respect to fecal matter.Particularly, when the wearer is in a sitting position, the frequency ofsideways leakage of highly fluidic, high velocity fecal matter pastconventional containment structures is problematic.

Therefore, what is lacking and needed in the art is an absorbent articlethat is adapted to contain fecal matter, and in particular highlyfluidic material that is expelled at high velocities.

SUMMARY OF THE INVENTION

In response to the discussed deficiencies in the prior art, a newabsorbent article has been developed. The absorbent article providesenhanced protection against leakage of fecal matter.

In one aspect, the present invention concerns an absorbent articlehaving longitudinal and transverse axes, longitudinal end edges, andlongitudinal side edges extending between the longitudinal end edges.The absorbent article also includes a moisture barrier, an absorbentassembly disposed on the moisture barrier, and fecal containment memberspositioned transversely outward of the absorbent assembly between theabsorbent assembly and each longitudinal side edge. The fecalcontainment members have a wet compression recovery of at least about 85percent and a mean pore size of at least about 1.5 millimeters.

The fecal containment members function to interrupt lateral movement offecal matter. The fecal containment members are formed of porousmaterials to provide sufficient void volume to collect highly fluidicfecal matter. Also, the fecal containment members desirably are dryresilient and wet resilient to maintain the void volume even after thediaper is insulted with urine and the wearer is in a sitting position.

In another aspect, the present invention concerns an absorbent articlehaving longitudinal and transverse axes and including a moisturebarrier, an absorbent assembly disposed on the moisture barrier, and abodyside liner bonded to the moisture barrier and sandwiching theabsorbent assembly therebetween. Containment flaps are disposed on themoisture barrier transversely outward of the absorbent assembly, witheach containment flap having a base and a distal edge and definingtherebetween a flap height. The base is spaced from the absorbentassembly by at least about 5 millimeters. Fecal passage members of theabsorbent article each have an inner portion bonded to the bodysideliner, and an outer portion bonded to one of the containment flaps at anattachment point spaced from the base by from about 25 and about 95percent of the flap height. As a result, fecal reservoirs are definedbetween the absorbent assembly, the containment flaps, the fecal passagemembers, and the moisture barrier.

This aspect provides a diaper with a pair of longitudinally extendingfecal reservoirs. The reservoirs provide void spaces transverselyoutward of the absorbent assembly to contain fecal matter. The fecalpassage members form part of the fecal reservoirs by maintainingportions of the containment flaps spaced from the absorbent assembly andbodyside liner. The fecal passage Embers are adapted to permit fecalmatter to pass therethrough into the fecal reservoirs.

Numerous features and advantages of the present invention will appearfrom the following description. In the description, reference is made tothe accompanying drawings which illustrate preferred embodiments of theinvention. Such embodiments do not represent the full scope of theinvention. Reference should therefore be made to the claims herein forinterpreting the full scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 representatively shows a top plan view of a disposable absorbentarticle according to the present invention, in a stretched and laid flatcondition and with portions broken away for purposes of illustration.

FIG. 2 representatively shows an enlarged transverse section view takengenerally from the plane of the line 2--2 in FIG. 1, although in arelaxed condition rather than the stretched condition.

FIG. 3 representatively shows an enlarged transverse section viewillustrating portions of an alternative absorbent article according tothe present invention, in a relaxed condition.

FIG. 4 representatively shows an enlarged transverse section viewillustrating portions of another alternative absorbent article accordingto the present invention, in a relaxed condition.

FIG. 5 representatively shows an enlarged transverse section viewillustrating portions of a further alternative absorbent articleaccording to the present invention, in a relaxed condition.

FIG. 6 representatively shows an enlarged transverse section viewillustrating portions of a still further alternative absorbent articleaccording to the present invention, in a relaxed condition.

DEFINITIONS

Within the context of this specification, each term or phrase below willinclude the following meaning or meanings:

(a) "bonded" refers to the joining, adhering, connecting, attaching, orthe like, of two elements. Two elements will be considered to be bondedtogether when they are bonded directly to one another or indirectly toone another, such as when each is directly bonded to intermediateelements.

(b) "disposable" includes being disposed of after use and not intendedto be washed and reused.

(c) "disposed," "disposed on," "disposed with," "disposed at," "disposednear" and variations thereof are intended to mean that one element canbe integral with another element, or that one element can be a separatestructure bonded to or placed with or placed near another element.

(d) "elastic," "elasticized" and "elasticity" mean that property of amaterial by virtue of which it tends to recover its original size andshape after removal of a force causing a deformation.

(e) "elastomeric" refers to a material or composite which can beelongated by at least 25 percent of its relaxed length and which willrecover, upon release of the applied force, at least 10 percent of itselongation. It is generally preferred that the elastomeric material orcomposite be capable of being elongated by at least 100 percent, morepreferably by at least 300 percent, of its relaxed length and recover,upon release of an applied force, at least 50 percent of its elongation.

(f) "extension," "extend" and "extended" mean the change in length of amaterial due to stretching, expressed in units of length.

(g) "fabrics" is used to refer to all of the woven, knitted and nonwovenfibrous webs.

(h) "flexible" refers to materials which are compliant and which willreadily conform to the general shape and contours of the wearer's body.

(i) "force" includes a physical influence exerted by one body on anotherwhich produces acceleration of bodies that are free to move anddeformation of bodies that are not free to move. Force is expressed ingrams per unit area.

(j) "hydrophilic" describes fibers or the surfaces of fibers which arewetted by the aqueous liquids in contact with the fibers. The degree ofwetting of the materials can, in turn, be described in terms of thecontact angles and the surface tensions of the liquids and materialsinvolved. Equipment and techniques suitable for measuring thewettability of particular fiber materials or blends of fiber materialscan be provided by a Cahn SFA-222 Surface Force Analyzer System, or asubstantially equivalent system. When measured with this system, fibershaving contact angles less than 90° are designated "wettable" orhydrophilic, while fibers having contact angles greater than 90° aredesignated "nonwettable" or hydrophobic.

(k) "inward" and "outward" refer to positions relative to the center ofan absorbent garment, and particularly transversely and/orlongitudinally closer to or away from the longitudinal and transversecenter of the absorbent garment.

(l) "layer" when used in the singular can have the dual moaning of asingle element or a plurality of elements.

(m) "liquid impermeable" when used to describe a layer or laminate meansthat liquid such as urine will not pass through the layer or laminateunder ordinary use conditions in a direction generally perpendicular tothe plane of the layer or laminate at the point of liquid contact.

(n) "member" when used in the singular can have the dual meaning of asingle element or a plurality of elements.

(o) "nonwoven web" means a web of material which is formed without theaid of a textile weaving or knitting process.

(p) "operatively joined" and "operatively connected," with reference tothe attachment of an elastic member to another element, means that theelastic member when attached to or connected to the element, or treatedwith heat or chemicals, by stretching, or the like, gives the elementelastic properties; and with reference to the attachment of anon-elastic member to another element, means that the member and elementcan be attached in any suitable manner that permits or allows them toperform the intended or described function of the joinder. The joining,attaching, connecting or the like can be either directly, such asjoining either member directly to an element, or can be indirectly bymeans of another member disposed between the first member and the firstelement.

(q) "stretch bonded" refers to an elastic member being bonded to theanother member while the elastic member is extended at least about 25percent of its relaxed length. Desirably, the term "stretch bonded"refers to the situation wherein the elastic member is extended at leastabout 100 percent, and mere desirably at least about 300 percent, of itsrelaxed length when it is bonded to the other member.

(r) "stretch bonded laminate" refers to a composite material having atleast two layers in which one layer is a gatherable layer and the otherlayer is an elastic layer. The layers are joined together when theelastic layer is in an extended condition so that upon relaxing thelayers, the gatherable layer is gathered.

These terms may be defined with additional language in the remainingportion of the specification.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIGS. 1 and 2, an absorbent article formed accordingto the present invention is shown for purposes of illustration as adisposable diaper 20. The invention may also be embodied in other typesof absorbent articles such as adult incontinence garments, children'straining pants, or the like. The diaper 20 includes fecal containmentmembers 60 that are positioned and adapted to collect fecal matter, andthereby minimize the likelihood of leakage.

The illustrated diaper 20 defines longitudinal and transverse axes,represented by arrows 22 and 24 in FIG. 1. The diaper 20 has opposite,front and back longitudinal end edges 26 and 27, and longitudinal sideedges 28 that extend between the longitudinal end edges. The diaper 20includes a first or front waist region 30, a second or back waist region32, and an intermediate, crotch region 34 positioned between andinterconnecting the front and back waist regions. The outer edges of thediaper 20 define a periphery 36 in which the longitudinally extendingside margins are designated 38 and the laterally extending end marginsare designated 39. The side edges 28 define leg openings for the diaper20, and optionally, are curvilinear and contoured. The end edges 26 and27 are shown as generally straight, but optionally, may be curvilinear.

The front waist region 30 is contiguous with the front end edge 26 andextends longitudinally inward therefrom toward the transverse centerline of the diaper 20. The back waist region 32 is contiguous with theback end edge 27 and extends longitudinally inward therefrom toward thetransverse center line. The waist regions 30 and 32 comprise those upperportions of diaper 20 which, when worn, wholly or partially cover orencircle the waist or mid-lower torso of the wearer. The intermediate,crotch region 34 comprises that portion of diaper 20 which, when worn,is positioned between the legs of the wearer and covers the lower torsoof the wearer. Thus, the crotch region 34 is the area where insults ofurine and fecal matter typically occur in the diaper or other disposableabsorbent article.

The diaper 20 includes a substantially liquid impermeable moisturebarrier 40, an absorbent assembly 42 disposed on the moisture barrier,and a substantially liquid permeable bodyside liner 44 bonded to themoisture barrier to sandwich the absorbent assembly therebetween. Themoisture barrier 40 and bodyside liner 44 are desirably longer and widerthan the absorbent assembly 42 so that the peripheries of the moisturebarrier and bodyside liner may be bonded together using ultrasonicbonds, thermal bonds, adhesives, or other suitable means. Theperipheries of the moisture barrier 40 and the bodyside liner 44typically form the side and end margins 38 and 39 of the diaper 20. Theabsorbent assembly 42 may be bonded directly to the moisture barrier 40and/or the bodyside liner 44 using ultrasonic bonds, thermal bonds,adhesives, or other suitable means.

The moisture barrier 40 desirably comprises a material that is formed ortreated to be liquid impermeable. Alternatively, the moisture barrier 40may comprise a liquid permeable material and other suitable means (notshown), such as a liquid impermeable layer associated with the absorbentassembly 42, may be provided to impede liquid movement away from theabsorbent assembly. The moisture barrier 40 may also be gas permeable,such that gases encountered during use of the absorbent garment are ableto pass through the material under ordinary use conditions, over eitherall or part of its surface area.

The moisture barrier 40 may comprise a single layer of material or alaminate of two or more separate layers of material. Suitable moisturebarrier materials include films, wovens, nonwovens, laminates of films,ovens, and/or nonwovens, or the like. For example, the moisture barrier40 may comprise a thin, substantially liquid impermeable web or sheet ofplastic film such as polyethylene, polypropylene, polyvinyl chloride orsimilar material. The moisture barrier material may be transparent oropaque and have an embossed or matte surface. One particular materialfor the moisture barrier 40 is a polyethylene film that has a nominalthickness of about 0.025 millimeter and a systematic matte embossedpattern, and that has been corona treated on both sides. Anothersuitable moisture barrier material is an adhesive or thermal laminatecomprising a cast or blown film formed of polypropylene, polyethylene orthe like, and a spunbond web formed of polypropylene fibers orpolypropylene and polyethylene medium-crimped btcomponent fibers in a50/50 side-by-side configuration,

The absorbent assembly 42 comprises materials adapted to absorb andretain liquid waste. The absorbent assembly 42 may comprise variousabsorbent materials, such as an air-formed bait of cellulosic fibers(i.e., wood pulp fluff) or a coform material composed of a mixture ofcellulosic fibers and synthetic polymer fibers. The absorbent assembly42 may also include compounds to increase its absorbency, such as 0-95weight percent of organic or inorganic high-absorbency materials, whichare typically capable of absorbing at least about 15 and desirably morethan 25 times their weight in water. Suitable high-absorbency materialsare described in U.S. Pat. No. 4,699,823 issued Oct. 13, 1987, toKellenberger et al. and U.S. Pat. No. 5,147,343 issued Sep. 15, 1992, toKellenberger, which are incorporated herein by reference.High-absorbency materials are available from various commercial vendors,such as Dow Chemical Company, Hoechst Celanese Corporation, and AlliedColloids, Inc. The absorbent assembly 42 may also include tissue layersor acquisition or distribution layers to help maintain the integrity offibrous absorbents or transport liquids (not shown).

The bodyside liner 44 is formed of a liquid permeable material so thatliquid waste, and possibly semi-solid waste as well, can pass throughthe liner and be absorbed by the absorbent assembly 42. Suitablebodyside liners 44 may comprise a nonwoven web or sheet of wet strengthtissue paper, a spunbonded, meltblown or bonded-carded web composed ofsynthetic polymer filaments or fibers, such as polypropylene,polyethylene, polyesters or the like, or a web of natural polymerfilaments or fibers such as rayon or cotton. In addition, the bodysideliner 44 is desirably nonelastic and may be treated with a surfactant toaid in liquid transfer. In a particular embodiment of the invention, theliner 44 comprises a nonwoven, spunbond polypropylene fabric composed ofabout 2.8-3.2 denier fibers formed into a web having a basis weight ofabout 22 gsm and density of about 0.06 gm/cc. The fabric is surfacetreated with about 0.28 weight percent of a surfactant commerciallyavailable from Rohm and Haas Co. under the trade designation TritonX-102.

The diaper 20, which is in a stretched and laid flat condition in FIG.1, is illustrated as having a periphery 36 that is hourglass or Ishaped. Of course, the diaper 20 may optionally be T-shaped,rectangular, or irregularly-shaped. The general shape of the absorbentassembly 42 may correspond to the shape of the diaper 20 or assume adifferent shape such as the T-shape in FIG. 1. Desirably although notnecessarily, the diaper 20 also includes elastic members in severallocations to maintain the periphery 36 of the diaper 20 against thewearer and minimize the potential for leakage.

Elongated leg elastic members 46 are longitudinally oriented in eachside margin 38, extending toward the front and back end edges 26 and 27.The leg elastic members 46 are positioned in the illustrated embodimentbetween the moisture barrier 40 and the bodyside liner 44. Usingultrasonic bonds, adhesives, thermal bonds, or other suitable means, theleg elastic members 46 are attached in a stretched condition to themoisture barrier 40, the bodyside liner 44, or both, in either astraight or a curved shape. The leg elastic members 46 can be arrangedto draw and hold the side margins 38 of the diaper 20 against the legsof the wearer and form a seal therewith.

The diaper 20 may also include waist elastic members 48 (FIG. 1) in theend margins 39. The waist elastic members 48 are longitudinally orientedparallel to the transverse axis 24 of the diaper 20 to provideelasticized waists. Desirably, the waist elastic members 48 arepositioned between the moisture barrier 40 and the bodyside liner 44 andsecured in an extended condition to both the moisture barrier and theliner, using ultrasonic bonds, adhesives, thermal bonds or othersuitable means.

The elastic members 46 and 48 may be formed of a dry-spun coalescedmultifilament elastomeric thread sold under the tradename LYCRA andavailable from E. I. Du Pont de Nemours and Company. Alternately, theelastic members 46 and 48 may be formed of other typical elasticsutilized in the diaper-making art, such as a thin ribbon of naturalrubber, a stretch bonded laminate material comprising a prestretchedelastic meltblown inner layer sandwiched between and bonded to a pair ofspunbond polypropylene nonwoven webs, or the like. Elasticity could alsobe imparted to the absorbent article by extruding a hot melt elastomericadhesive between the moisture battle; 40 and the liner 44. Othersuitable elastic gathering means are disclosed in U.S. Pat. Nos.4,938,754 to Mesek and 4,388,075 to Mesek et al.

Refastenable tape members 50 (FIG. 1) are operably connected to the sidemargins 38 in the back waist region 32 of the diaper 20. Each tapemember 50 includes a fastening strip that may be releasably attached toan optional tape landing pad 52 located in the front waist region 30.The landing pad 52 is fixed by adhesive or other suitable means to thesurface of the moisture barrier 40 that is remote from the absorbentassembly 42. The tape members 50 and the landing pad 52 are positionedso that the fastening strips may be attached to the landing pad when thediaper 20 is secured on a baby.

The tape members 50 and the landing pad 52 may be formed of a filmcomprising polypropylene, biaxially oriented polypropylene, polyester,or the like, and may be constructed in a manner as disclosed in U.S.Pat. No. 4,753,649 issued Jun. 28, 1988, to Pazdernik, which isincorporated herein by reference to the extent it is consistentherewith. Other suitable fastening devices, such as hooks, snaps,cohesive strips and the like, could be used in place of the tape members50 and the landing pad 52.

In general, the moisture barrier 40, absorbent assembly 42, bodysideliner 44, elastic members 46 and 48, and fastening system components 50and 52 of the diaper 20 may be assembled in a variety of well-knowndiaper configurations. Further, the diaper 20 may include othercomponents in addition to those specifically illustrated. In particular,alternative diaper configurations which include additional features aredisclosed in U.S. patent application Ser. No. 08/168,615 by T. Roessleret al., filed Dec. 16, 1993, and titled "Dynamic Fitting Diaper"(Attorney Docket No. 10,961); and U.S. patent application Ser. No.08/168,615 by E. D. Johnson et el., filed Aug. 12, 1994, and titled"Diaper With Improved Lateral Elongation Characteristics" (AttorneyDocket No. 11,629).

As referenced previously, the diaper 20 of FIGS. 1 and 2 also includesfecal containment members 60 which function to interrupt the lateralmovement of high velocity fecal matter. Desirably formed of a porousresilient material, the fecal containment members 60 provide void volumeto collect highly fluidic fecal matter. The fecal containment members 60are desirably both dry resilient and wet resilient to maintainsufficient void volume even after the diaper 20 is insulted with urine,and even after the wearer is in a sitting position which tends to putpressure on the fecal containment members. The fecal containment members60 may be bonded to the bodyside liner 44 using ultrasonic bonds,thermal bonds, adhesives, or other suitable means.

The illustrated fecal containment members 60 are in the shape of agenerally straight bar but may alternatively be in the shape of acylinder, strip, cube, or the like and be curved or partially curved.The shape of the fecal containment members 60 desirably provides a highvoid volume obstacle to sideways movement of fecal matter. Thus, thefecal containment members 60 desirably have a width dimension measuredparallel to the transverse axis 24 of from about 5 to about 50millimeters, and particularly from about 15 to about 25 millimeters forimproved performance.

Further, the fecal containment members 60 desirably have a heightdimension perpendicular to the plane containing the longitudinal andtransverse axes 22 and 24 that is greater than the height dimension ofthe absorbent assembly 42. For example, the fecal containment members 60may have a height dimension that is at least about 5 millimeters greaterthan the height dimension of the absorbent assembly 42. In particularembodiments, the width and height dimensions are selected so that thefecal containment members 60 have a cross sectional area measuredparallel to the transverse axis 24 of at least about 2.5 squarecentimeters, and particularly from about 7.5 to about 12.5 squarecentimeters for improved performance.

The fecal containment members 60 desirably extend less than the entiredistance between the front and back end edges 26 and 27 and areselectively positioned in the region where the absorbent assembly 42 islocated. In the illustrated embodiment, the fecal containment members 60are located in the crotch region 34 and in the back waist region 32 atleast near the back end edge of the absorbent assembly 42.Alternatively, the fecal containment members 60 may extend the entirelength dimension of the diaper 20 (not shown). In particularembodiments, the fecal containment members 60 have a length dimension offrom about 24 to about 34 centimeters.

As shown in FIG. 1, the fecal containment members 60 maybe positionedtransversely outward of the absorbent assembly 42 in the crotch region34 and on top of the absorbent assembly in the front waist region 30.Alternatively, the fecal containment members 60 may be positionedexclusively on top of the absorbent assembly 42 or exclusivelytransversely outward of the absorbent assembly (not shown). In any case,the fecal containment members 60 are desirably spaced from one anotherand located away from the longitudinal axis 22 so that fecal matter islikely to be expelled at a location which is between the members 60. Inparticular, the fecal containment members 60 are desirably spaced fromone another by at least about 5 centimeters (cm), such as from about 5to about 12 cm. The absorbent assembly 42 of the diaper 20 desirably hasa width dimension in the crotch region 34 that is relatively narrow,such as from about 5 to about 9 cm.

Various materials can be used to construct the fecal containment members60. For example, the fecal containment members 60 maybe a nonwoven webof fibers, a foam, or any other suitable material which provides thedesired function. The fecal containment members 60 may be asubstantially hydrophobic material and, optionally, can be treated witha surfactant or otherwise to impart a desired level of wettability andhydrophilicity.

If the fecal containment members 60 comprise a foam material, any typeof polymer which can be foamed and which can provide the desiredfunction can be used. For example, the fecal containment members 60 maycomprise an open-celled foam material made from polystyrene,polyvinylchloride, polyethylene, polyolefins, polyurethane,polyisocyanates, polyphenols, epoxy resins, silicon resins and the like.The foam material may also be rigid, semi-rigid or flexible. In aparticular aspect of the invention, the fecal containment members 60comprise a semi-rigid, polyurethane open-celled foam material.

Methods of forming such foam materials are well known to those skilledin the art. As is well known to those skilled in the art, the physicalproperties of the resultant foam materials can be varied broadly bycontrolling the ingredients and processing of the foam materials.Following the foaming of the polymer, the structure of the foam can alsobe modified by processes known to those skilled in the art to provide agreater number of open cells in the cell structure. For example, thepercentage of open cells in the foam material can be increased to asgreat as 99 percent or higher. Foam materials having greater than 95percent open cells are generally known as "reticulated" foams. Foammaterials having an increased number of open cells are particularlydesired for the fecal containment members 60 of the present invention ina particular aspect of the invention, the fecal containment members 60comprise a polyurethane foam material wherein at least 80 percent anddesirably at least 95 percent of the cells present in the foam are opencells. For example, the fecal containment members 60 may comprise apolyurethane foam material designated Style #80,000 Federal Foam whichis commercially available from Illbruck, Inc., a business having officeslocated in Minneapolis, Minn.

In a particular aspect of the invention, the fecal containment members60 have a density (determined at a load of 0.2 psi) which is not morethan about 0.050 grams per cubic centimeter and desirably from about0.010 to about 0.030 grams per cubic centimeter to provide improvedperformance. Desirably, the fecal containment members 60 also have abasis weight of from about 100 to about 200 grams per square meter andmore desirably from about 125 to about 175 grams per square meter.Moreover, the fecal containment embers 60 are desirably substantiallyfree of high-absorbency material such as absorbent gelling material suchthat the fecal containment members 60 do not retain high amounts ofliquid.

The fecal containment members 60 may also be configured to have a meanpore size of at least about 1.5 millimeters and desirably from about toabout 4.0 millimeters. If the mean pore size is too small, fecal mattermay not enter the void volume provided by the fecal containment members60. The mean pore size can be determined according to any of variousmethods known to those skilled in the art. One such method is the PoreSize Test as set forth in the TEST PROCEDURES section below.

The fecal containment members 60 of the present invention function tohold the discharged fecal matter until the diaper 20 is removed. In oneaspect of the present invention, it is particularly useful for the fecalcontainment members 60 to maintain a sufficient amount of void volumeeven when under load. For instance, the fecal matter should not beforced from the fecal containment members 60 when the wearer is in aposition which causes pressure to be exerted on the containment members.Also, the fecal containment members 60 should continue to present anobstacle to lateral movement of fecal matter even when under load. Thevoid volume of the fecal containment members 60 will vary as the loadexerted upon it varies. As used herein, the term "void volume" refers tothe void volume value as determined according to the void volumeequation set forth in the Wet Compression Recovery Test in the TESTPROCEDURES section below.

In a particular aspect of the invention, the fecal containment members60 have a void volume which is at least about 20 cubic centimeters pergram and desirably from about 30 to about 50 cubic centimeters per gramwhen under no compressive load. In addition, the diaper 20 can includesufficiently sized fecal containment members 60 to provide a void volumeof at least about 3.0 cubic centimeters and desirably from about 5.0 toabout 9.0 cubic centimeters under no load to provide improvedperformance. For example, the fecal containment members 60 may includeabout 0.2 grams of a polyurethane foam material having a void volume(under no load) of about 36 cubic centimeters per gram to provide about7.2 cubic centimeters of void volume when under no load.

The fecal containment members 60 are also desirably both wet and dryresilient to preserve the void volume after exposure to urine and evenafter being compressed by the wearer. The resiliency of the fecalcontainment members 60 maybe represented by the ability of the materialto recover its original volume after being compressed. In a particularaspect, the fecal containment members 60 have a wet compression recoveryof at least about 85 percent, desirably from about 90 to about 100percent and more desirably from about 95 to about 100 percent. As usedherein, the term "wet compression recovery" refers to the compressionrecovery value determined according to the Wet Compression Recovery Testas set forth in the TEST PROCEDURES section below. It is also desirablethat the fecal containment members 60 maintain at least about 25percent, desirably from about 30 to about 100 percent, and even moredesirably from about 50 to about 100 percent of their void volume (underno load) when under a load of 0.673 Newtons per square centimeter (0.975pounds per square inch).

To enhance the containment and absorption of urine and facilitatecontainment of fecal matter, the diaper 20 of FIGS. 1 and 2 canoptionally include a pair of containment flaps 70. The flaps 70, whichextend longitudinally between the front and back end edges 26 and 27 ofthe diaper 20, are disposed on the moisture barrier 40 and positionedtransversely inward of the side edges 28 and the leg elastic members 46.The fecal containment members 60 are desirably positioned immediatelytransversely inward of the containment flaps 70. Configurations ofcontainment flaps 70 suitable for use on the illustrated diaper 20 aredisclosed in U.S. Pat. Nos. 4,704,116 and 4,846,823 to Enloe, and U.S.patent application Ser. No. 208,816 of R. Everett et al., filed Mar. 4,1994 and entitled "ABSORBENT ARTICLE HAVING AN IMPROVED SURGEMANAGEMENT" (Attorney docket No. 11,375), the disclosures of which arehereby incorporated by reference in a manner that is consistentherewith.

With specific reference to FIG. 2, the containment flaps 70 may beformed as a folded, elongated strip of material. The containment flaps70 may, for example, comprise an attachment portion 72 along onelongitudinal edge and a folded portion 73 along the oppositelongitudinal edge. Elastic members 74 may be operatively joined to thecontainment flaps 70 within the folded portions 73, thereby causing theflaps to stand up from the bodyside liner 44 when the diaper 20 is worn.The particular number of elastic members 74 per containment flap 70 andthe type of elastic material may vary. Suitable materials include a thinribbon of elastic material or several strands of elastic string. Eachelastic member 74, for instance, can be a dry-spun, coalescedmultifilament elastomeric thread sold under the tradename LYCRA andavailable from E. I. Du Pont de Nemours and Company.

The attachment portion 72 of each containment flap 70 can be attached tothe bodyside liner 44 using a continuous ultrasonic bond, a continuousstrip of adhesive, a series of spot bonds, or other suitable means.Alternatively, the containment flaps 70 could be formed in portions ofthe bodyside liner (not shown). The longitudinal ends of eachcontainment flap 70 are desirably laid flat on the bodyside liner 44toward the longitudinal axis 22 and bonded to the bodyside liner. Theregion of the attachment portion 72 nearest the medial part of thecontainment flap 70 that is not bonded to the bodyside liner 44 isdesignated the base 76 of the flap. Oppositely, the part of thecontainment flap 70 that extends furthest from the bodyside liner 44when the diaper 20 is worn is designated the distal edge 78 of the flap.The distance between the base 76 and the distal edge 78 defines a flapheight of the containment flap 70, which is desirably greater than theheight dimension of the fecal containment members 60, such as at leastabout 5 millimeters (mm) greater than the height dimension of the fecalcontainment members.

In use, the diaper 20 is positioned on the wearer and secured in placewith the tape members 50. The fecal containment members 60 function toprevent leakage of fecal matter initially by providing an obstacle tolateral movement of fecal matter and then by providing a containmentmechanism for the fecal matter. The large pore size of the containmentmembers 60 make them well adapted to accept high velocity, highlyfluidic fecal matter. Additionally, the resiliency of the containmentmembers 60 allows them to remain effective under load. The containmentflaps 70, when employed, provide further assistance in limiting lateralmovement of fecal matter.

An alternative embodiment of the invention is illustrated by a diaper 80shown in a partial transverse section view in FIG. 3. Components similarto those previously described have been given the same referencenumeral. In this embodiment, the bodyside liner 44 is positioned overthe fecal containment members 60 so that the fecal containment membersare disposed between the bodyside liner and the moisture barrier 40. Atleast in the crotch region 34 of the diaper 20, the fecal containmentmembers 60 are desirably positioned transversely inward of thecontainment flaps 70.

The bodyside liner 44 of this embodiment is desirably formed or treatedto permit passage of highly fluidic fecal matter therethrough. Inparticular, the bodyside liner 44 may be formed with a relatively openpore structure, or may be treated, such as by pin aperturing, slit andtransverse-stretching, needle punching, or other suitable means, topermit passage of fluidic fecal matter. The treatment may encompass theentire bodyside liner 44 or only specific portions of the bodysideliner, such as those portions disposed on and near the fecal containmentmembers 60.

A further alternative embodiment is illustrated by a diaper 82 shown ina partial transverse section view in FIG. 4. The diaper 82 includes apair of fecal passage members 84, which are each bonded to the bodysideliner 44 and the adjacent containment flap 70, to form a pair oflongitudinally extending fecal reservoirs 86. The fecal reservoirs 86provide void spaces transversely outward of the absorbent assembly 42 tocontain fecal matter. While only one fecal passage member 84 and onereservoir 86 are illustrated in FIG. 4, it can be appreciated that theopposite side of the diaper 82 is constructed in a similar manner toprovide the second of the two fecal reservoirs.

The fecal passage members 84 function to form part of the fecalreservoirs 86, in part by maintaining portions of the containment flaps70 spaced from the absorbent assembly 42 and bodyside liner 44. Eachfecal reservoir 86 is formed with the absorbent assembly 42 and one ofthe containment flaps 70 functioning as sidewalls of the reservoir, themoisture barrier 40 functioning as the floor of the reservoir, and oneof the fecal passage members 84 functioning as the ceiling of thereservoir. It should be recognized of course that in this embodimentportions of the bodyside liner 44 reside within the reservoir 86.

The fecal passage members 84 may be formed of the same material as thefecal containment Embers 60 described in relation to FIGS. 1-3. Thefecal passage members 84 may, for instance, comprise a nonwoven web offibers, a foam, or any other suitable material which is generallyresilient and allows the passage of fecal matter therethrough. The fecalpassage members 84 may be a substantially hydrophobic material and,optionally, can be treated with a surfactant or otherwise to impart adesired level of wettability and hydrophilicity. In one embodiment, thefecal passage members 84 comprise a semi-rigid, polyurethane foammaterial wherein at least 80 percent and desirably at least 95 percentof the cells present in the foam are open cells. The fecal passagemembers 84 in such embodiment may have a width of about 1.5 cm, athickness (determined at a load of 0.2 psi) of about 0.5 cm, and alength of about 10 cm.

The fecal passage members 84 are suitably configured to have a mean poresize which allows fecal matter to pass easily therethrough. The poresize in particular is desirably at least about 1.5 millimeters anddesirably from about 2.0 to about 4.0 millimeters. Further, the fecalpassage members 84 are desirably both wet and dry resilient, and inparticular having a wet compression recovery of at least about 85percent, desirably from about 90 to about 100 percent and more desirablyfrom about 95 to about 100 percent. As used herein, the term "wetcompression recovery" refers to the compression recovery valuedetermined according to the Wet Compression Recovery Test as set forthin the TEST PROCEDURES section below. Moreover, the fecal passagemembers 84 are desirably substantially free of high-absorbency materialso that they do not retain high amounts of liquid.

The fecal passage members 84 each have an inner portion 87 bonded to thebodyside liner 44 and an outer portion 88 bonded to one of thecontainment flaps 70. The inner portion 87 is desirably bonded to thebodyside liner 44 at a first attachment point 89 that is located on topof the bodyside surface of the absorbent assembly 42 or along a sideedge of the absorbent assembly, as in FIG. 4, so that the region betweenthe inner portion 87 and the moisture barrier 40 forms a sidewall of thefecal reservoir 86. Similarly, the outer portion 88 is desirably bondedto the containment flap 70 at a second attachment point 90 that islocated between the base 76 and the distal edge 78. In particular, theouter portion 88 is suitably bonded to the containment flap 70 at anattachment point 90 that is spaced from the base 76 by from about 25 toabout 95 percent of the flap height, and more particularly by from about50 to about 75 percent of the flap height. As a result, the region ofthe containment flap 70 between the outer portion 88 and the moisturebarrier 40 forms another sidewall of the fecal reservoir 86. Also, theouter portion 88 is desirably attached to the containment flap 70 sothat the elastic member 74 of the containment flap is positioned betweenthe second attachment point 90 and the distal edge 78.

The size of the fecal reservoirs 86 is a function in part of where thecontainment flap 70 is directly (not shown) or indirectly (FIG. 4)bonded to the moisture barrier 40. Specifically, the size of thereservoirs 86 is determined in part by the spacing of the base 76 ofeach containment flap 70 from the side edge of the absorbent assembly42. Desirably, the base 76 of each containment flap 70 is spaced fromthe absorbent assembly 42 by at least about 5 millimeters (mm), and moreparticularly by at least about 8 mm, such as from about 10 to about 50mm for improved performance.

Another embodiment of the invention is shown as diaper 92 in the partialtransverse section view of FIG. 5. The diaper 92 includes a fecalpassage layer 94 which is disposed on the absorbent assembly 42. Thefecal passage layer 94 has an inner portion 87 positioned over theabsorbent assembly 42 and outer portions 88 located on either side ofthe inner portion.

Each outer portion 88, only one of which is shown in FIG. 5, is bondedto one of the containment flaps 70 at an attachment point 90 that islocated between the base 76 and the distal edge 78 of a flap. The outerportions 88 are suitably bonded to the containment flaps 70 at anattachment point 90 that is spaced from the base 76 by from about 25 toabout 95 percent of the flap height, and more particularly by from about50 to about 75 percent of the flap height. Because the base 76 of eachcontainment flap 70 is spaced from the absorbent assembly 42 by at leastabout 5 mm, and more particularly by at least about 8 mm, such as fromabout 10 to about 50 mm, fecal reservoirs 86 are formed transverselyoutward of the absorbent assembly 42 to contain fecal matter. The fecalpassage layer 94, which may be formed of the same material as the fecalpassage members 84 described in relation to FIG. 4, allows fecal matterto pass easily therethrough into the void volume of the fecal reservoirs86.

The illustrated embodiment also includes an optional bodyside liner 44disposed between the fecal passage layer 94 and the absorbent assembly42. Alternatively, the fecal passage layer 94 may be disposed directlyon the absorbent assembly 42 and function as a bodyside liner (notshown). The inner portion 87 of the fecal passage layer 94 may be bondedto the bodyside liner 44 by adhesives, thermal bonds, ultrasonic bonds,or other suitable means.

The alternative embodiment illustrated by diaper 96 in FIG. 6 is similarto the diaper 92 of FIG. 5, except that a pair of leakage guards 98(only one shown) are substituted for the bodyside liner 44. Each leakageguard 98, only one of which is shown, has an inner edge 99 positioned ontop of the absorbent assembly 42. The inner edge 99 is disposed betweenthe fecal passage layer 94 and the absorbent assembly 42 adjacent theperiphery of the absorbent assembly. The leakage guards 98 are desirablyformed of a liquid impermeable material and as a result tend to inhibitlateral movement of liquid.

TEST PROCEDURES Wet Compression Recovery Test

This test has been designed to measure the compression recovery of amaterial when it is wet. The wet compression recovery indicates theability of a material to recover to its original volume after beingsubjected to a compressing force. Wet compression recovery is determinedfrom void volume measurements and is measured using an INSTRON orSINTECH tensile tester which measures the resisting force as a materialis compressed between a movable platen and a fixed base at a constantrate using a certain amount of force and subsequently releasing theforce at the same rate.

Suitable equipment for this test could include:

Compression tester: INSTRON model 6021 with compression test softwareand 1 kN load cell made by Instron of Bucks, England.

Balance: Merrier of Highstown, N.J., model PM4600

Preferably pressure, or force, and platen position are recorded. If onlyforce is recorded, pressure is calculated using: ##EQU1## where:P=pressure in Pascals

F=force pushing back on the platen in Newtons

A_(p) =area of the platen in square centimeters (18.9 cm²)

Void volume for a given material is calculated as follows: ##EQU2##where: VV=void volume of the material sample in cubic centimeters pergram

Vol=volume of the material sample in cubic centimeters

M=mass of the material sample in grams

p_(fiber) =fiber density in grams per cubic centimeter

For materials made with multiple fiber types, the material fiber densityis the weight average of each individual fiber density:

    p.sub.fiber, Total =wt %.sub.fiber 1.p.sub.fiber 1 +wt %.sub.fiber 2.p.sub.fiber 2 + . . .

where:

wt %=weight percent of the fiber type in the material or ##EQU3##

When a foam material is being measured, p_(fiber) is the density of thematerial from which the foam is fabricated. For example, if the foammaterial is a polyurethane foam, p_(fiber) is the density ofpolyurethane. For foam materials, the void volume (VV) calculated usingthe preceding equation is an approximation and the actual void volumewill become less than the calculated void volume (VV) as the number ofclosed cells within the foam material increases.

The void volume of a material will vary as the load upon the materialvaries. The void volume of the material for a given platen position iscalculated using the void volume equation set forth above wherein:

    Vol=(x.sub.o -x).A.sub.m.0.1 cm/mm

where:

Vol=volume of material in cubic centimeters

X_(o) =initial platen position from the base in millimeters

x=platen position from initial position in millimeters

A_(m) =area of sample material in square centimeters

The base must be larger in size than the platen. Zero height betweenplaten and base distance was set by bringing the platen down until itbarely touches the base. The platen was then raised to the desiredinitial height from the zero distance. The initial platen position mustbe greater than the initial thickness of the sample material so that thetest starts out at zero pressure on the sample. The sample material canbe the same size as the platen or larger.

For the purpose of measuring wet void volume for the presentspecification, a 4.9 cm diameter circular platen was used to compressmaterials against the base at a rate of 5.08 mm/min up to a 1.32 kg load(6,900 Pascal or 1.00 lb/in² pressure). The platen was then returned atthe same rate to the initial starting position. The initial startingposition for the platen was the sample material thickness plus 1 mm fromthe base. Material samples were cut to 50.4 mm diameter circles and weretested in the center. Force and position data were recorded at uniformperiods of time between 0.05 and 0.01 minutes. The test is run on fivematerial samples and the results averaged.

Wet void volume was measured when the material sample was completelyimmersed in 0.9% aqueous saline throughout the test. A flat bottomedcontainer such as a hexagonal polystyrene weighing dish catalog #02-202DFrom Fischer Scientific of Pittsburgh, Pa. was placed on the base andthe platen was zeroed and set to the initial position as describedabove. A 0.9% aqueous saline solution was added to the container to fillit to a level just to the bottom of the platen at its initial position.An appropriate saline could be S/P certified blood bank saline made byStephens Scientific of Riverdale, N.J. and distributed by BaxterHealthcare of McGraw Park, Ill. under catalog #B3158-1. For the purposeof measuring void volume for the present specifications, 120 ml ofsaline was placed in the container and the platen was initially set adistance equal to 1 mm greater than the thickness of the test materialsample from the base.

The load cell was tared with this level of fluid in the container. Thesample was placed in the fluid, under the platen and the test was thenperformed as described above. Buoyant force was found to have anegligible effect on pressure but if so desired it can be subtractedfrom the pressure readings at each platen position using the followingequation: ##EQU4## where: P_(B) =Pressure from buoyant force in Pascals

P_(saline) =saline (fluid) density in grams per cubic centimeter

A_(p) =area of the platen in square centimeters (18.9 cm²)

A_(d) =area of the dish in square centimeters

x_(o) =initial platen position from the base in millimeters

x=platen position in millimeters

g=standard acceleration of gravity which is 981 cm/seconds²

0.01=conversion factor=0.1 cm/mm.0.001 kg/gm.100 cm/m

The overall pressure on the sample becomes:

    P.sub.sample =P.sub.reading.P.sub.B

where:

P_(sample) =pressure on the sample from the platen in Pascal

P_(reading) =pressure reading from the SINTECH or INSTRON in Pascal

P_(B) =buoyancy pressure from the 0.9% saline in Pascal

Wet compression recovery was calculated using the platen positions oninitial compression to 68.9 Pascal and on recovery when the pressure wasequal to 68.9 Pascal: ##EQU5## where: VV_(recovery) 68.9 Pa =void volumeupon recovery at 68.9 Pascal pressure

VV_(compress) 68.9 Pa =void volume upon initial compression to 68.9Pascal pressure

Pore Size Test

This test has been designed to measure the mean pore size of a sample ofmaterial which may be used in an absorbent article, such as an infantdiaper. The sample of material has a thickness of about 0.25 inches(0.64 centimeters), a width of about 2.0 inches (5.1 centimeters), and alength of about 2.5 inches (6.35 centimeters). The sample is placed on aglass microslide having a width of 2.0 inches (5.1 centimeters) and alength of 3.0 inches (7.62 centimeters). The surface of the sample iscoated with a 2:1 diluted solution of Pentel® Correction Fluid andisopropyl alcohol. The Pentel® Correction Fluid is commerciallyavailable from Pentel Co., Ltd., a business having offices located inJapan. The diluted solution migrates through the sample and is allowedto dry. The drying solution cements the sample to the glass microslide.

The microslide having the dried, coated sample adhered thereon is placedon a macroviewer stand and viewed through a 50 MM E1-Nikkor f/2.8enlarging lens. Lighting is provided by an 8-bulb octagonal ringilluminator that surrounds the lens to provide "incident darkfield"conditions. The mean pore size of the sample of material is determinedusing a Quantimet 970 Image Analyzer which is commercially availablefrom Leica Instruments, Inc., a business having offices located inDeerfield, Ill. Major cut polygons and minor window faces are selectedmanually with a "light pen" when they are approximately orthogonal tothe viewing plane. A program was developed to analyze the individualmeasurements and organize them into a histogram showing the total numberof pores, the mean pore size and the standard deviation of the poresize.

The foregoing detailed description has been for the purpose ofillustration. Thus, a number of modifications and changes may be madewithout departing from the spirit and scope of the present invention.For instance, alternative or optional features described as part of oneembodiment can be used to yield another embodiment. Additionally, twonamed components could represent portions of the same structure.Therefore, the invention should not be limited by the specificembodiments described, but only by the claims.

We claim:
 1. An absorbent article having longitudinal and transverseaxes, the absorbent article comprising:a moisture barrier; an absorbentassembly disposed on the moisture barrier; a bodyside liner bonded tothe moisture barrier and sandwiching the absorbent assemblytherebetween; containment flaps disposed on the moisture barriertransversely outward of the absorbent assembly, each containment flaphaving a base and a distal edge and defining therebetween a flap height,the base being spaced from the absorbent assembly by at least about 5millimeters; and fecal passage members each having inner and outerportions, the inner portions being bonded to the bodyside liner and theouter portions being bonded to one of the containment flaps at anattachment point spaced from the base by from about 25 and about 95percent of the flap height, fecal reservoirs being defined between theabsorbent assembly, the containment flaps, the fecal passage members,and the moisture barrier.
 2. The absorbent article of claim 1, whereinthe attachment point is spaced from the base by from about 50 to about75 percent of the flap height.
 3. The absorbent article of claim 1,wherein the base is spaced from the absorbent assembly by at least about8 millimeters.
 4. The absorbent article of claim 3, wherein the base isspaced from the absorbent assembly by from about 10 to about 50millimeters.
 5. The absorbent article of claim 1, wherein the fecalpassage members have a wet compression recovery of at least about 85percent.
 6. The absorbent article of claim 1, wherein an elastic memberis operatively joined to each containment flap between the attachmentpoint and the distal edge.
 7. The absorbent article of claim 1, whereinthe fecal passage members have a mean pore size of at least about 1.5millimeters.
 8. An absorbent article having longitudinal and transverseaxes, the absorbent article comprising:a moisture barrier; an absorbentassembly disposed on the moisture barrier; containment flaps disposed onthe moisture barrier transversely outward of the absorbent assembly,each containment flap having a base and a distal edge and definingtherebetween a flap height, the base being spaced from the absorbentassembly by at least about 5 millimeters; and a fecal passage layerdisposed on the absorbent assembly and having an inner portion and outerportions located on opposite sides of the inner portion, each of theouter portions being bonded to one of the containment flaps at anattachment point spaced from the base by from about 25 and about 95percent of the flap height, fecal reservoirs being defined between theabsorbent assembly, the containment flaps, the fecal passage layer, andthe moisture barrier.
 9. The absorbent article of claim 8, wherein theattachment point is spaced from the base by from about 50 to about 75percent of the flap height.
 10. The absorbent article of claim 8,wherein the base is spaced from the absorbent assembly by at least about8 millimeters.
 11. The absorbent article of claim 10, wherein the baseis spaced from the absorbent assembly by from about 10 to about 50milliliters.
 12. The absorbent article of claim 8, further comprising aliquid permeable liner between the fecal passage layer and the absorbentassembly.
 13. The absorbent article of claim 8, further comprising apair of liquid impermeable leakage guards bonded to the moisturebarrier, the leakage guards having inner edges disposed between thefecal passage layer and the absorbent assembly.